With expeditious development of network and technologies, the virtual reality industry also develops rapidly. Various manufacturers have launched their own virtual reality helmets. However, different virtual reality helmets generally have different structures and use different optical lens. This causes sizes and contents of an image to be viewed different when different virtual reality helmets are worn.
For a virtual reality helmet integrally designed with an in-built screen, it is possible to adjust an imaging range and effect of the screen during a process of manufacturing the helmet. However, for a virtual reality helmet that needs a mobile phone placed inside as a screen, it is impossible for the helmet to be well adapted to the mobile phones of all models. For example, when a mobile phone with a larger size is put inside, it is quite possible that the mobile phone's screen is larger than a user's visual range; as a consequence, content viewed by the user will be incomplete. Such a problem might also arise even for a same mobile phone when being used in different virtual reality helmets. This seriously dampens user experience.